"""
分析：判断A是否是质数方式：A除以2到A-1的所有数，是否都不被整数。
"""
num = int(input('>>>'))
if num <= 2:
    print(num, 'is prime number')
else:
    for i in range(2, num):
        if num % i == 0:
            print(num, 'is not prime number')
            break
    else:
        print(num, 'is prime number')
